1/4 MOA Riddle

[MidTennFisher]

While sighting in a rifle last week I shot two bullets that went about 3" left, 1" high at almost 100 yds. My scope is a Vortex Diamondback with 1/4 MOA.

So I adjusted 12 clicks to the right, 4 clicks down. Shot a bullet and it was roughly 3" to the right, 1" low. Basically, it flipped. Not what I expected...

Ok, so I backed up halfway. Adjusted 6 clicks back to the left, 2 clicks back up. Shot two bullets within half an inch of the bullseye.

What did I miss here? I admit I am not a guru when it comes to rifle scopes but the math isn't that complicated. If my scope is 1/4 MOA and I shoot 3" to the left at almost 100 yds, then shouldn't 12 clicks to the right get it in the center?

If I'm misunderstanding something I'd certainly like to know!

 

[Jcalder]

The scope doesn't track properly.

 

[Remi]

The scope doesn't track properly.

Winner!

 

[Jcalder]

Also, moa at 100 yards is 1.047". Not really enough to matter but 12 clicks should do it. But if you're short of that it may only take 11 clicks, depending how short of 100. Either way, that scope isn't moving as it should

 

[MidTennFisher]

The scope doesn't track properly.

Ok so it's an issue with the scope, not the user?

Not a huge deal, I'll just remember it for the future.

 

[DaveTN]

Ok so it's an issue with the scope, not the user?

We can't know that.

If you picked up another scoped rifle, fired 5 shots and could cover them with an eraser like these guys do, then we would know.

 

[nso123]

You can always run a tracking test if you have the time and extra ammo. I have also found that some scopes need to be turned a click or two past where you are trying to adjust it to, then go back to where you want it. You'll find that a lot of scopes don't track as advertised.

 

[Jcalder]

We can't know that.

If you picked up another scoped rifle, fired 5 shots and could cover them with an eraser like these guys do, then we would know.

It's just a plain fact it isn't working as it should. I could add a lot more, but won't.

 

[DaveTN]

It's just a plain fact it isn't working as it should. I could add a lot more, but won't.

You can't call that fact with 5 shots.

 

[Jcalder]

You can't call that fact with 5 shots.

You're exactly right, but assuming the gun will shoot MOA, which is wrong of me but for a different discussion, that scope still isn't tracking right. Even if it'll group 1.5 moa, it's borderline tracking ok.